Steam boiler



May 30, 1933. H. C HEATQN 1,912,197

STEAM BOILER Filed Nov. 1925 2 Sheets-Shet l Figl INVENTOR a, Alf-ah Y 7%WFM A TTORNEY May 30, 1933. H, c HEATON 1,912,197

STEAM BOILER Filed Nov. 1925 ZSheets-Sheet .2

Fig15 INVENTOR A TTORNEYS Patented May 38, 1933 STATES HERMAN C. HEATON, OF CHICAGO, ILLINOIS STEAM BOILER Application file-c1 November My present invention relates to steam boilers, and particularly to means for avoiding difiiculties arising from the use of 1111 pure feed water, and will be best understood 5 from the following description and the annexed drawings in which Fig. 1 is a side sectional elevation of an illustrative embodiment of a steam boiler embodying my invention, the section being taken on the line 1-1 of Fig. 2 and some of the parts being shown more or less diagrammatically; and Fig. 2 is a rear elevation of the boiler shown in Flg.

1, with some of the parts shown more or less diagrammatically.

Like reference characters indicate like parts in the difierent views.

In the illustrative arrangement, a steam boiler having water tubes 10, connected to uptake headers 11 and downtake headers 12, is positioned above the furnace chamber 13,

the fuel in which is burned on the chain grate stoker 14. The headers are connected to the steam and water drum 15, the steam from which is led to the superheater 16.

My invention is not concerned with the specific form of steam boiler and further description of the boiler illustrated will not be necessary.

At the rear of the boiler is an economizer 17 which may be of any of the well-known forms and, as illustrated in Fig. 1, it is of the form shown in Jacobus Patent No.

1,329,767, granted February 3, 1920, in which M headers are located on opposite sides of the flue and are connected by tubes extending across the flue. A pipe 18 is connected to the lowermostheader of the economizer and the water irom this pipe flows upward through the economizer to the outlet 19, from which it flows through the pipe 20 to the steam and water drum 15. A valved pipe 21 connecting i the pipes 18 and may be used to direct the water supply from pipe 18 to pipe 20, and from thence to the drum 15 without passing through the economizer, the pipes 18 and 20 also being provided with valves for this purpose. 7

In the illustrative embodiment, there is provided at the upper part of the flue in which the economizer 17 is located and where 9,1925. Serial No. 67,737.

it will be contacted first by the waste gases coming from the boiler tubes 10, an evaporator 31 which, in the illustrative form, is also made up of headers connected by tubes precisely as in the form of economizer illustrated, This evaporator section has a water inlet 22 and a water outlet 23, the latter being connected'to a small steam and water drum 24 from which a pipe 25 controlled by a valve 26 leads to the steam space of the drum 15. The inlet 22 is connected through a pipe 27 with a pump 28, the pipe 27 being provided with a hand valve 29 and an automatic control valve 30. Water from the pump 28 passes through the pipe 27 into the evaporator 31 and if any of the water is not evaporated, it flows with the steam from the evaporator into the drum 24. The steam passes through the pipe 25 into the drum 15' and i there mingles with the steam' produced by the steam boiler proper.

The Water in the drum 24 is preferably maintained at a predetermined level, and to this end, I provide a water-level controlling device ofa well-known form, in which a tube inside of a jacket 32 is connected by a pipe 33 with the steam space of the drum 15 and by a pipe 34 with the water space in the drum 24, a fluid in the jacket 32 exerting pressure through a tube 35 to the 30 automatic control valve 30, by which the flow of water past the valve 30 is controlled so as to maintain the water level in the drum 2 Lsubstantially constant. The water-level regulator which I have used for purposes of illustration, is a well-knowninstrumentality now used for the maintenance of water levels in boilers, and further description thereof will be unnecessary for those skilled in the. art.

With the arrangement described, it will be obvious that the heating surface of the evaporator 31 is contacted by relatively cool gases. It will also be obvious that none of the water from the evaporator 81 reaches the boiler drum 15eXcept in the form of steam, which ofcourse, is pure. Consequently, if arelatively impure water supply only is available, such'water can be first evaporated in the evaporator 31 before passing into the boiler,

thus avoiding the necessity of frequent cleaning of the boiler tubes and, moreover, avoiding the possibility of injury of such tubes because of the high heat to which they are subjected, such high heat making it extremely undesirable to have solid deposits in such tubes. On the other hand, any deposits in the tubes of the evaporator 31 can be more readily cleaned than can the'boiler tubes, and because of the lower temperature to which the evaporator tubes are subjected, there is less liability to injury because of such deposits. Moreover, the solids inthe evaporator are not so likely to deposit as they are in the boiler because, by an outlet 36 on the drum 24, which outlet is controlled by a valve 37, I can arrange the parts so that a certain amount of water will be condrum, a valved connection to said drum whereby water may be continuously Withdrawn from the drum, and automatic means to supply water to said evaporator at a rate to maintain the water level in said drum substantially constant.

HERMAN C. HEATON tinuously drawn ofi from the drum 24, so 7.

that the tendency is for the solids to be carried with the water through the evaporator in the drum 24, and from thence through the outlet 36. If desired, instead of keeping the valve 37 partially open so as to maintain a. continuous blowdown, it is obvious that the valve 37 may be opened from time to time for the same purpose.

hen the arrangement which I have just described is used, as it usually will be, in a power generating system of the usual type in which the steam from the boiler, after passing through the prime mover, is condensed and the condensate returned to the boiler, it will be obvious that the only water which need be added to the system is such make-up water as will be necessary to replace the small amount of water which escapes in the form of steam or otherwise from this theoretically closed cycle. In such a system, the condensate will be fed to the economizer 17 through the pipe 18 and the make-up water will be supplied by the pump 28 to the evaporator, this water passing into the closed cycle in the form of steam only.

By the arrangement which I have described, there are no heat losses and pure water only is fed to the boiler by an extremely simple arrangement. While preferably I arrange the evaporator 31 where it will be contacted by gases of relatively low temperature, it will be understood that my invention is not limited to such a construc tion. It will also be understood that the various features of the economizer and the boiler which are shown are merely illustrative and can be varied without departing from the principles of my invention. a It will also be understood that the particular form of the evaporator can be widely varied.

I claim: 7

A steam boiler, an evaporator heated by the boiler gases after they have passed over tween the evaporator and the steam space of the boller, including a steam and water the boiler heating surface, a oonnectionbe- 

